The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure. Unless otherwise indicated herein, the approaches described in this section are not prior art to the claims in the present disclosure and are not admitted to be prior art by inclusion in this section.
Solid state drives (SSDs) are built using a plurality of flash memory dice (e.g., NAND flash memory dice). In some drives, one of the memory dice is used to store redundancy information, for example, parity data consisting of a running Exclusive OR (XOR) total for corresponding blocks of data of the other memory dice. This parity data may be used to recover data in the event of a defect on one of the memory dice. However, an entire memory die must be dedicated for storage of parity data.